For background on AOS systems see Corrado et al., U.S. Pat. No. 5,482,314 and our copending divisional case Ser. No. 08/731,355, filed Oct. 11, 1996. Such systems produce a signal for input to the ADS, which if the occupant is out of position (OOP) or in a rear facing infant seat (RFIS) in the front seat of a vehicle, the deployment of the airbag is aborted, deferred or otherwise controlled, as in SAS.
One of the substantive factors to be considered is the fact that air currents set up within the vehicle near the IP can interfere with or cause anomalous readings of ultrasound (US) sensors. In addition, streams of heated or cold conditioned air can interfere with or cause short duration signal ambiguities of Infra Red (IR) sensors. The former tends to be long term, i.e., US anomalies so long as blower is on, while the IR tends to be transient.